A sintered body includes a first hard particle, a second hard particle, and a binder. The first hard particle is an M sialon particle having a coating layer. The M sialon particle is represented by MxSi(6−x−z)AlzOzN(8−z) (in the formula, M is a metal containing at least one selected from the group consisting of calcium, strontium, barium, scandium, yttrium, lanthanoid, manganese, iron, cobalt, nickel, copper, and group IV, group V, and group VI elements of the periodic table, and relationships of 0.01≤x≤2, 0.01≤z≤4.2, and 1.79≤(6−x−z)≤5.98 are satisfied). The second hard particle is a cubic boron nitride particle.